Mass transfer devices, such as oxygenators and dialyzers, are known in which the mass transfer device housing encloses a heat exchanger for controlling the temperature of the blood. For example, a combination blood oxygenator and heat exchanger is disclosed in U.S. Pat. No. 3,764,271.
Although the heat exchanger of the present invention may be used in many different fields, and although no limitation is intended, for simplicity the heat exchanger of the present invention will be described herein as being used in a blood oxygenator. Disposable blood oxygenators are widely used today in connection with the oxygenation of a patient's blood, and the present invention is ideally suited for this field of use, among others.
It is desirable that a disposable blood oxygenator be relatively compact, have a low prime volume, be easy to manufacture, and have a relatively low cost. It is important that a heat exchanger, used in connection with a disposable blood oxygenator, enable substantially uniform flow of the fluids that will be in heat exchange relationship with each other. It is also desirable that the oxygenator and heat exchanger be formed as a single unit, that the heat exchanger be positioned close to the oxygenating medium, such as the oxygenator fiber bundle, and that the heat exchanger have high efficiency with a relatively low pressure drop.
The present invention provides a heat exchanger having the characteristics and abilities set forth above.